Efﬁcacy of dexmedetomidine on postoperative shivering: a ...Hua Xia, and Zui Zou were involved in the study conduct. Zhen-Xiu Liu, Feng-Ying Xu, Xiao Liang, Jing-Ru Wu, Miao Zhou,

REVIEW ARTICLE/BRIEF REVIEW

Efficacy of dexmedetomidine on postoperative shivering:a meta-analysis of clinical trials

Efficacité de la dexmédétomidine pour contrôler les frissonspostopératoires: une méta-analyse d’études cliniques

Zhen-Xiu Liu, BSc • Feng-Ying Xu, BSc • Xiao Liang, BSc • Miao Zhou, BSc •

Liang Wu, BSc • Jing-Ru Wu, MD • Jian-Hua Xia, MD • Zui Zou, MD

Received: 23 June 2014 / Accepted: 18 March 2015 / Published online: 8 April 2015

� Canadian Anesthesiologists’ Society 2015

Abstract

Purpose Shivering is a frequent complication in the

postoperative period. The aim of the current meta-analysis

was to assess the efficacy of dexmedetomidine on

postoperative shivering.

Methods Two researchers independently searched

PubMed, EMBASETM and the Cochrane Central Register

of Controlled Trials for controlled clinical trials. The meta-

analysis was performed by Review Manager.

Results Thirty-nine trials with 2,478 patients were

included in this meta-analysis. Dexmedetomidine reduced

postoperative shivering compared with placebo (risk ratio

[RR] = 0.26; 95% confidence interval [CI]: 0.20 to 0.34),

with a minimum effective dose of 0.5 lg�kg-1 (RR = 0.36;95% CI: 0.21 to 0.60). The anti-shivering effect can be

achieved both intravenously and epidurally when

administered within two hours prior to the end of

surgery. The efficacy of dexmedetomidine was similar to

widely used anti-shivering agents, such as fentanyl,

meperidine, tramadol, clonidine and so on; however,

dexmedetomidine may increase the incidence of sedation,

hypotension, bradycardia and dry mouth.

Conclusions The present meta-analysis indicates that

dexmedetomidine shows superiority over placebo, but not

over other anti-shivering agents. Therefore, considering its

high price and potential adverse events, dexmedetomidine

may not be appropriate solely for the purpose of the

prevention of postoperative shivering.

Résumé

Objectif Les frissons sont une complication fréquente en

période postopératoire. L’objectif de cette méta-analyse

était d’évaluer l’efficacité de la dexmédétomidine pour

contrôler les frissons postopératoires.

Author contributions Zhen-Xiu Liu, Feng-Ying Xu, Xiao Liang,and Zui Zou were involved in the study design. Feng-Ying Xu, Jian-Hua Xia, and Zui Zou were involved in the study conduct. Zhen-XiuLiu, Feng-Ying Xu, Xiao Liang, Jing-Ru Wu, Miao Zhou, and LiangWu were involved in data retrieval and analysis. Zhen-Xiu Liu, Feng-Ying Xu, and Zui Zou were involved in writing the paper.

Zhen-Xiu Liu, Feng-Ying Xu, Xiao Liang contributed equally to this

work.

Z.-X. Liu, BSc � M. Zhou, BSc � L. Wu, BSc � J.-R. Wu, MD �Z. Zou, MD

Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou

Medical College, Xuzhou, People’s Republic of China

Z.-X. Liu, BSc � M. Zhou, BSc � L. Wu, BSc � J.-R. Wu, MD �Z. Zou, MD

Jiangsu Province Key Laboratory of Anesthesia and Analgesia

Application Technology, Xuzhou Medical College, Xuzhou,

People’s Republic of China

Z.-X. Liu, BSc � J.-H. Xia, MD (&)Department of Anesthesiology, No. 411 Hospital of PLA,

Shanghai, People’s Republic of China

e-mail: [email protected]

F.-Y. Xu, BSc � Z. Zou, MD (&)Department of Anesthesiology, Changzheng Hospital,

Second Military Medical University, Shanghai,

People’s Republic of China

e-mail: [email protected]

X. Liang, BSc

Department of Anesthesiology, Affiliated People’s Hospital of

Jiangsu University, Zhenjiang, People’s Republic of China

123

Can J Anesth/J Can Anesth (2015) 62:816–829

DOI 10.1007/s12630-015-0368-1

http://crossmark.crossref.org/dialog/?doi=10.1007/s12630-015-0368-1&domain=pdfhttp://crossmark.crossref.org/dialog/?doi=10.1007/s12630-015-0368-1&domain=pdf

Méthode Deux chercheurs ont analysé de façon

indépendante les bases de données PubMed, EMBASETM

et le registre central d’études contrôlées Cochrane

(Cochrane Central Register of Controlled Trials) pour en

extraire les études cliniques contrôlées pertinentes. La

méta-analyse a été réalisée avec Review Manager.

Résultats Trente-neuf études comportant un total de

2478 patients ont été incluses dans cette méta-analyse. La

dexmédétomidine a réduit les frissons postopératoires par

rapport au placebo (risque relatif [RR] = 0,26; intervalle

de confiance [IC] 95 % : 0,20 à 0,34), avec une dose

efficace minimum de 0,5 lg�kg-1 (RR = 0,36; IC 95 % :0,21 à 0,60). L’effet anti-frissons peut être obtenu par voie

intraveineuse et péridurale lorsque l’agent est administré

dans les deux heures précédant la fin de la chirurgie.

L’efficacité de la dexmédétomidine était semblable à celle

d’agents anti-frissons fréquemment utilisés tels que le

fentanyl, la mépéridine, le tramadol et la clonidine;

toutefois, la dexmédétomidine pourrait augmenter

l’incidence de sédation, d’hypotension, de bradycardie et

de sécheresse buccale.

Conclusion Cette méta-analyse indique que la

dexmédétomidine démontre une supériorité par rapport

au placebo, mais pas par rapport à d’autres agents

anti-frissons. Par conséquent, au vu de son prix élevé et de

ses effets secondaires néfastes potentiels, la

dexmédétomidine peut ne pas être appropriée si le seul

but est de prévenir les frissons postopératoires.

Shivering is a physiological response of the body for heat

preservation through peripheral vasoconstriction and

involuntary skeletal muscle contractions.1 Despite the

benefits from reducing heat loss, shivering increases the

patients’ oxygen consumption, carbon dioxide production,

and energy expenditure,2 and it may cause severe adverse

effects during the recovery from general anesthesia,

especially in patients with impaired cardiac and

pulmonary reserves. Moreover, for awake patients,

shivering is an uncomfortable experience, sometimes

even worse than surgical pain.3 Effective prevention and

treatment of shivering has become an essential step in

increasing postoperative comfort and reducing shivering-

related complications. Currently used anti-shivering agents

are restricted by their side effects. For example, meperidine

may induce nausea, vomiting, and respiratory depression,4

and patients receiving ketamine5 frequently experience

hypertension and tachycardia.

Dexmedetomidine is a potent and highly selective

a2-adrenoceptor agonist with sympatholytic, sedative,amnestic,6 and analgesic7 properties. Clinical researchers

have already studied the administration of

dexmedetomidine to prevent shivering. Nevertheless,

controversy about the effectiveness of dexmedetomidine

for the prevention of shivering is still ongoing, with

different results reported in associated literature. In our

view, a quantitative analysis on a consolidation of the

related data was needed, and therefore, we conducted the

present meta-analysis in order to assess the relative merits

regarding the anti-shivering effect of dexmedetomidine.

Methods

This meta-analysis of controlled trials evaluates the effect

of intraoperative dexmedetomidine on postoperative

shivering and was performed according to the

recommendations of the PRISMA statement.

Search strategy

Two authors (L.Z.X and X.F.Y.) systematically searched

PubMed, EMBASETM and the Cochrane Central Register

of Controlled Trials (CENTRAL). The search strategy

comprised the following key words: (dexmedetomidine)

and (shivering, shiver, tremor, shaking, or anti-shivering)

and (postoperative, operation, surgery, anesthesia, or

anaesthesia). The literature search was updated on

August 30, 2014 with no language limitation. The

reference lists of the reviews, original reports, and case

reports (retrieved through the electronic searches) were

checked to identify studies that had not yet been included

in the computerized databases.

Study selection and data retrieval

The study selection criteria were pre-established. Inclusion

criteria included: (1) controlled clinical trials; (2)

intraoperative administration of dexmedetomidine; and

(3) the reported presence or absence of shivering.

Exclusion criteria included: (1) abstracts only; (2)

patients with severe cerebrovascular disease or other

contradictions for dexmedetomidine; (3) duplications; (4)

missing data; and (5) incorrect statistical analysis

performed in the report. The data retrieval included:

name of the first author, publication year, funding,

interventions, patients and operations, type of anesthesia,

length of surgery, number of shivering cases and total

patients, randomization, blinding, allocation concealment,

withdrawal, body temperature, and side effects such as

nausea, vomiting, and hypotension. Two authors (L.Z.X.

and X.F.Y.) independently assessed the articles for

compliance with the inclusion/exclusion criteria. Any

Efficacy of dexmedetomidine for postoperative shivering 817

123

disagreement during the process of meta-analysis was

resolved by discussion among all authors.

Qualitative assessment

Two authors (L.X. and Z.M.) independently evaluated the

quality of the trials according to the guidelines

recommended by the Cochrane Collaboration.8 Six

categories were evaluated, with the first three considered

as ‘‘key domains’’ (randomization and sequence

generation, allocation concealment, blinding method,

incomplete outcome data, selective outcome reporting,

and other sources of bias). Each category was summarized

into three levels: low risk, unclear risk, and high risk. The

risk of bias of a particular study was assessed in relation to

the three key domains: LOW (low risk of bias for all key

domains); UNCLEAR (unclear risk of bias for one or more

key domains); and HIGH (high risk of bias for one or more

key domains).

Statistical analysis

The effect of dexmedetomidine on postoperative shivering

compared with placebo or other anti-shivering drugs was

estimated by calculating the pooled risk ratio (RR) and its

95% confidence intervals (CI) of the incidence of

shivering. The overall effect was determined by a Z-test.

All reported P values are two sided. A fixed effects model

was used when I2 B 50%, otherwise a random effects

model was adopted. Sensitivity analysis was performed to

test the robustness of the results by re-analyzing the data

after excluding the high-risk studies. Subgroup analyses

were based on the types of anesthesia, the doses and routes

administered, and the A-E interval (defined as the time

interval from the last administration to the end of the

operation. Two-hour duration was used as the cut-off point,

because the half-life of dexmedetomidine is about two

hours).9 Begg’s test was conducted to assess potential

publication bias. Statistical analysis was performed with

Review Manager (RevMan version 5.3; Cochrane

Collaboration, Oxford, UK) and Stata� version 12.0

(Stata Corp, College Station, TX, USA).

Results

Study selection

As shown in the flow diagram (Fig. 1), the search of

PubMed, EMBASE, CENTRAL, and the reference lists

yielded 237 articles. Initially, 166 trials were discarded

because they were not controlled trials according to the

titles, and after reviewing the abstracts, an additional 21

trials were excluded as they were not relevant to our study.

We could not retrieve the full texts of three10-12 of the

remaining 50 papers despite attempting electronic retrieval

interlibrary loan or contacting the authors. After carefully

reading 47 papers, we excluded eight with no related

endpoints. Finally, 39 trials3,9,13-49 met the selection

criteria and were included in the meta-analysis.

Study characteristic

Twenty-two of the included studies explored the efficacy of

intraoperative dexmedetomidine compared with place-

bo.3,9,13-32 Other control agents included fentanyl,33-36 remifen-

tanyl,37,38 meperidine,15 midazolam,39-41 propofol,43,44

ketamine,45,46 tramadol,24,47 clonidine,42 propacetamol,48 and

buprenorphine49 (Table 1). Twenty studies reported the side

effects, including sedation,4,13,22,28,31 nausea,9,14,20,22,23,27,29,30

vomiting,14,22,23 bradycardia,17,20,23,26-28,30-32 hypoten-

sion20,23,26-28,30,32 and dry mouth.14,22,23 Only eight of the

included articles clearly mentioned the funding status, five of

which3,21,22,35,37 were supported by an institutional foundation,

and three studies23,44,47 declared no financial support.

The methodological quality of the included studies

Thirty3,13,14,16,19-21,23,24,26-33,35-38,40-44,46-49 of the 39 includ-

ed trials provided a detailed description of randomization.

Odd/even admission number was used in the process of ran-

domization in three trials.9,25,45 Twenty-nine

trials3,9,13,14,16,19,21,23,27-31,33-38,41-44,47-49 reported allocation

concealment, and 27 studies39,13,14,16,19,24,25,27-35,37-42,44,47-49

were double-blinded. No incomplete outcomes (attrition

bias)8 were reported in the 39 included trials, and all

studies reported every endpoint mentioned in the Methods

section (reporting bias).8 however, some bias8 may exist in

of the two trials,27,32 as the length of surgery was not clear.

An overview of the risk of bias is summarized in Fig. 2.

Results of the meta-analysis

Dexmedetomidine versus placebo

Twenty-two trials3,9,13-32 including 1,415 patients inves-

tigated the anti-shivering efficacy of dexmedetomidine

compared with placebo. The incidence of postoperative

shivering in the dexmedetomidine group was significantly

lower than in the placebo group (34.2% vs 8.6%,

respectively; pooled RR = 0.26; 95% CI: 0.20 to 0.34)

(Fig. 3). Begg’s test suggested no significant publication

bias (P = 0.128) in this comparison between

dexmedetomidine and placebo.

Furthermore, dexmedetomidine can significantly reduce

postoperative nausea and vomiting (PONV) compared with

818 Z.-X. Liu et al.

123

placebo (data not shown). Nevertheless, compared with

placebo, dexmedetomidine increased the probability of

sedation (pooled RR of five trials: 2.94; 95% CI: 2.18 to

3.98), bradycardia (pooled RR of nine trials: 2.39; 95% CI:

1.54 to 3.72), hypotension (pooled RR of seven trials: 1.35;

95% CI: 1.04 to 1.75), and dry mouth (pooled RR of three

trials: 7.33; 95% CI: 2.28 to 23.58) (Table 2).

Subgroup analyses were carried out to evaluate the

factors that affected postoperative shivering.

Types of anesthesia Dexmedetomidine significantly

reduced the incidence of shivering in general anesthesia

(pooled RR of 12 trials:3,13-23 0.26; 95% CI: 0.20 to 0.34)

and regional anesthesia (pooled RR of ten trials:9,24-32 0.27;

95% CI: 0.16 to 0.45) (Fig. 3). The most common

dexmedetomidine dosage was 1.0 lg�kg–1, so we chosethis group in one trial.1

The A-E interval The incidence of shivering in groups

with an A-E interval less than two hours was reduced by

dexmedetomidine (pooled RR of 18 trials: 0.24; 95% CI:

0.19 to 0.32) compared with placebo (Fig. 4); however,

only one trial30 was conducted with an A-E interval more

than two hours in which no statistical difference in the

incidence of shivering could be found between

dexmedetomidine and placebo (P = 0.64).

Dose of dexmedetomidine Subgroup analysis suggested a

beneficial effect of a single-dose bolus of 0.5 lg�kg-1dexmedetomidine compared with placebo (pooled RR of

three trials: 0.36; 95% CI: 0.21 to 0.60). A sensitivity analysis

to remove a high-risk study21 (high risk of bias for one or

more key domains, refer to Methods section) showed a similar

result favouring dexmedetomidine (pooled RR = 0.52; 95%

CI: 0.31 to 0.87) and decreased heterogeneity (I2 from 73%

to 42%). One trial19 presented that 0.75 lg�kg-1dexmedetomidine reduced the incidence of shivering with a

reported P value of 0.002. A subgroup of dexmedetomidine

1.0 lg�kg-1 also reduced the incidence of shivering (pooledRR of six trials: 0.24; 95% CI: 0.16 to 0.37) (Fig. 5).

Routes of administration Dexmedetomidine injected

intravenously (pooled RR of 17 trials: 0.24; 95% CI: 0.18

to 0.31) or into the epidural space (pooled RR of three trials:

0.28; 95% CI: 0.11 to 0.72) lowered the incidence of

shivering; however, two trials evaluating dexmedetomidine

injected into the subarachnoid space showed no difference

compared with placebo (pooled RR = 1.57; 95% CI: 0.45 to

5.54) (Fig. 6). Sensitivity analysis was performed excluding

the article30 with an A-E interval more than two hours (no

difference from placebo) to minimize heterogeneity. A

similar result favouring dexmedetomidine was found

(pooled RR = 0.13; 95% CI: 0.03 to 0.52) with almost no

heterogeneity across studies (I2 = 0%).

Fig. 1 Flow diagram of theinclusion and exclusion process


123

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13

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123

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123

Dexmedetomidine vs other anti-shivering agents

Nineteen studies,15,24,33-45,47-49 involving 1,063 patients,

compared the efficacy of dexmedetomidine with other drugs

on postoperative shivering. No significant difference could

be found between dexmedetomidine and other agents,

including fentanyl, remifentanyl, meperidine, midazolam,

ketamine, tramadol, clonidine, buprenorphine, or

propacetamol, except propofol (pooled RR = 0.33; 95%

CI: 0.11 to 0.98) (Table 3). Nevertheless, one of the articles

comparing dexmedetomidine with propofol was assessed

and had a high risk of bias. Therefore, the superiority of

dexmedetomidine over propofol was not reliably assessed.

Our systematic review showed that dexmedetomidine

not only has an anti-shivering effect, but it may also

increase hemodynamic stability during a sudden increase in

stress (e.g., intubation, skin incision, extubation), provide a

deeper level of sedation, decrease PONV, and prolong

postoperative analgesia compared with different agents

(Table 4). Of importance, however, recovery and

orientation time (patients’ response to questions regarding

time, place, and person) after tracheal extubation was

prolonged with dexmedetomidine when compared with

certain other agents (Table 4).

Discussion

Postoperative shivering frequently causes uncomfortable

feelings and is complicated by such complications as

tachycardia, hypertension, and cardiac ischemia, which can

lead to severe consequences. There is still an urgent need to

find an effective way to prevent or control postoperative

shivering.

The present meta-analysis was undertaken to evaluate the

efficacy of dexmedetomidine in the prevention of

postoperative shivering. The main findings are as follows:

(1) Dexmedetomidine shows superiority over placebo in the

prevention of postoperative shivering, but not over other

anti-shivering agents. (2) The beneficial effect can be

achieved through both intravenous and epidural injection.

Nevertheless, the time interval between the last

administration and the end of surgery should be less than

two hours, which is about the half-life of dexmedetomidine.

(3) While a 1.0 lg�kg-1 bolus dose is the most commonlyused in the published articles, a 0.5 lg�kg-1 bolus infusioncan still have a preventive effect. (4) Physicians should be

cautious about the side effects of dexmedetomidine, such as

sedation, bradycardia, hypotension, and dry mouth.

The anti-shivering effect of dexmedetomidine may be

mediated primarily by the a2b-drenoceptor, in the hypotha-lamus. Dexmedetomidine suppresses the spontaneous firing

rate of neurons, decreases the central thermosensitivity,14Fig. 2 Summary of the risk of bias of the included studies


123

and finally reduces the vasoconstriction and shivering

thresholds.50

Several elements for the clinical use of dexmedetomidine

should be considered. Kim et al.19 recommended the

minimum effective dose of 0.75 lg�kg-1 for adults.Furthermore, Bozgeyik et al.24 did not find any difference

between 0.5 lg�kg-1 dexmedetomidine and placebo;however, this investigation was hampered by a relatively

small sample size (30 patients per group). Based on the data of

relevant trials, we found that 0.5 lg�kg-1 dexmedetomidinewas sufficiently effective to prevent postoperative shivering.

Our finding that epidural dexmedetomidine, not spinal, is an

Table 2 Incidence of various side effects of dexmedetomidine vs placebo

Side effects Number of studies Number shivering/total number of patients RR (95%CI) References

Dexmedetomidine Placebo

Sedation 5 104/170 35/170 2.94 (2.18 to 3.98) 13,14,22,28,31

Bradycardia 9 52/252 21/253 2.39 (1.54 to 3.72) 17,20,23,26-28,30-32

Hypotension 7 70/198 52/199 1.35 (1.04 to 1.75) 20,23,26-28,30,32

Dry mouth 3 21/105 2/105 7.33 (2.28 to 23.58) 14,22,23

CI = confidence interval; RR = risk ratio

Fig. 3 Results of subgroup analysis of the incidence of postoperative shivering by anesthesia types


123

available option for anti-shivering might cause confusion,

since subarachnoid administration has always been

considered a faster and more effective approach compared

with the epidural route. We speculate that the injected dose

may be responsible. Spinal administration of 4-5 lg ofdexmedetomidine compared with epidural administration of

1.0 lg�kg-1 may not be enough to activate the receptorsinhibiting shivering.28

Fig. 4 Results of subgroup analysis of the incidence of postoperative shivering by the A-E intervals (defined as the time interval from the lastadministration to the end of the operation)

Fig. 5 Results of subgroup analysis of the incidence of postoperative shivering by doses of intravenous dexmedetomidine


123

Despite its analgesic, sedative, antiemetic, and anti-

shivering properties, dexmedetomidine increased the risk of

these side effects. Somnolence, one of the most dangerous

complications, although rare, has been reported resulting

from an overdose of dexmedetomidine.51 Moreover, the

price of dexmedetomidine is considerably higher than other

drugs. Consequently, we do not recommend the use of

dexmedetomidine solely for the purpose of preventing


A previous meta-analysis1 suggested an inferior role of

dexmedetomidine compared with some ‘‘more efficacious

agents’’ like meperidine, tramadol and nefopam.

Nevertheless, the results of the analysis are inconclusive,

as there were only two trials involving dexmedetomidine

with just 160 patients, and there was no direct comparison

between dexmedetomidine and the other agents. In contrast,

we included 39 articles, adopted a wide range of clinically

relevant outcome variables, and focused on direct

comparison in order to reach a solid conclusion.

This is a novel meta-analysis regarding the use of

dexmedetomidine for anti-shivering and an evaluation of

the factors that might influence its effectiveness. Most of

the included trials were well designed and reported with

low risk of bias. Moreover, we compared dexmedetomidine

directly with other anti-shivering agents and excluded

studies with a high risk of bias through sensitivity analysis.

All of these strategies enhanced the reliability of our

conclusion. Nevertheless, this meta-analysis has several

limitations. First, only eight trials3,21-23,35,37,44,47 reported

the source of their funding; and therefore, we did not know

Fig. 6 Results of subgroup analysis of the incidence of postoperative shivering by routes of dexmedetomidine administration


123

whether the other trials were supported by industry, which

could make the design prone to show the drug in its best

light. Second, body temperature was detected by various

techniques throughout the literature and we failed to

include this as an evaluation item.

In conclusion, the present meta-analysis indicated that

the administration of dexmedetomidine may prevent the

incidence of postoperative shivering, although there was no

difference compared with other anti-shivering drugs, such

as fentanyl, meperidine, tramadol, and clonidine. Our

results provided evidence to extend the clinical value of

dexmedetomidine beyond its routine usage for sedation and

analgesia. Nevertheless, due to its relatively high price and

potential side effects, we do not recommend that

anesthesiologists or perioperative medical staff use

dexmedetomidine solely for the purpose of preventing


Declaration of conflict of interest The authors declare no financialinterests relating to patents or shareholdings in corporations involved

in the medical market.

Funding The study was supported by the Shanghai Chen-Guangprogram (10CG40), Shanghai Health Bureau (XYQ2011022),

National Natural Science Foundation of China (30772092), and

Natural Science Foundation of Shanghai (14ZR1413700).

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Table 3 Incidence of postoperative shivering with dexmedetomidine compared with other anti-shivering drugs

Drugs Number of studies Number shivering/total number of patients RR (95%CI) References

Dexmedetomidine Control

Fentanyl 4 8/115 16/115 0.52 (0.25 to 1.07) 33-36

Remifentanyl 2 10/50 14/50 0.93 (0.19 to 4.64) 37,38

Meperidine 1 6/40 4/40 1.50 (0.46 to 4.91) 15

Midazolam 3 15/120 13/121 1.10 (0.29 to 4.17) 39-41

Propofol 2 3/42 10/42 0.33 (0.11 to 0.98) 43,44

Ketamine 2 2/39 0/39 3.00 (0.33 to 27.23) 45,46

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Clonidine 1 1/25 2/25 0.50 (0.05 to 5.17) 42

Buprenorphine 1 5/30 2/30 2.5 (0.53 to 11.89) 49

Propacetamol 1 0/15 4/15 0.11 (0.01 to 1.90) 48

CI = confidence interval; RR = risk ratio.

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Drugs Hemodynamics* Sedation Nausea and

vomiting

Postoperative analgesia and

consumption of analgesic

Recovery time Orientation

time

Heart rate

Fentanyl Unstable33,36 Lower34 Higher34 Shorter and more34-36 No difference33,35 - -

Remifentanyl Unstable37 Lower38 - Shorter and more38 - - -

Meperidine - Lower15 - - - Shorter15 -

Midazolam Unstable39 Lower41 Higher40 - Longer40 - -

Propofol - - - - Shorter43 - -

Ketamine Unstable45 - - - Longer45,46 - Quicker45,46

Tramadol - Lower24 Higher47 - - - -

Clonidine - Lower42 - - - - -

Buprenorphine - - - Shorter and more49 - - -

Propacetamol - Lower48 - - - - -

*Hemodynamics were recorded when patients experienced tracheal intubation, skin incision, tracheal extubation, or other sudden increase in

stress


123

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Efficacy of dexmedetomidine on postoperative shivering: a meta-analysis of clinical trialsEfficacité de la dexmédétomidine pour contrôler les frissons postopératoires: une méta-analyse d’études cliniquesAbstractPurposeMethodsResultsConclusions

RésuméObjectifMéthodeRésultatsConclusion

MethodsSearch strategyStudy selection and data retrievalQualitative assessmentStatistical analysis

ResultsStudy selectionStudy characteristicThe methodological quality of the included studiesResults of the meta-analysisDexmedetomidine versus placeboTypes of anesthesiaThe A-E intervalDose of dexmedetomidineRoutes of administration

Dexmedetomidine vs other anti-shivering agents

DiscussionReferences

Documents

Efﬁcacy of dexmedetomidine on postoperative shivering: a ...Hua Xia, and Zui Zou were involved in the study conduct. Zhen-Xiu Liu, Feng-Ying Xu, Xiao Liang, Jing-Ru Wu, Miao Zhou,